Joint source and channel optimized block TCQ with layered transmission and RCPC
Hongzhi Li, Chang Wen Chen · 2002
We present a fixed length block trellis coded quantization (TCQ) image coding method with layered transmission and rate compatible punctured convolutional codes (RCPC) for noisy channel image communication. Employing optimal bit allocation and TCQ, this fixed length coding scheme achieves a good compression ratio while avoiding the loss of synchronization between encoder and decoder in a noisy environment. The loss of synchronization, caused often by entropy coding in the presence of channel noise leads to catastrophic decoding errors and degrades the coding performance substantially. With layered transmission and RCPC protection, the experiments show that the PSNR performance degrades gradually compared with the schemes layered operation as the channel bit error rate increases.